EVERETT — The Snohomish County Jail is canceling its contracts to house inmates for police departments in other counties.

Other efforts to reduce overcrowding at the jail have come up short, and more drastic change is needed, Sheriff Ty Trenary said Thursday. Earlier this week, he sent cancellation notices to 18 police departments in King and Skagit counties.

“We now need to focus on the needs of the cities and the county,” he said, “and the only way to do that is to eliminate the outside users.”

The jail still will house inmates booked by police departments in Snohomish County and by federal, state and tribal agencies. The change comes amid a series of reforms at the jail, where health and safety concerns have drawn scrutiny in recent years.

The number of inmates held at the jail with medical issues or mental illness is “particularly concerning,” Trenary wrote in the letters.

“The demand for special housing and staff intensive care has outpaced our ability to provide it to an acceptable level,” he wrote.

In 2013, inmates from other counties on any given day filled an average 158 of the jail’s 1,200 beds, according to the sheriff’s office. That dipped to about 76 inmates in December, after the jail began enforcing stricter booking requirements.

Trenary at times has limited bookings for misdemeanor nonviolent offenders, especially when the jail is nearly filled to capacity. He’s also questioned the practice of using the jail to warehouse people with mental illness who have been arrested for minor offenses, such as unlawful camping.

Through its contracts, the sheriff’s office bills police departments in other counties to hold inmates. In 2013, those bills amounted to $4.3 million.

“We know that there will be a loss in revenue,” Trenary said. “We’re working really hard to determine how we can save money before we spit out a number” on how much the potential loss will be.

Snohomish County taxes are paying for the jail, and the costs of housing other counties’ inmates hasn’t always matched the revenue that comes in, Trenary said.

“We should not be focused on revenue as much as we should be on staff and inmate safety,” he said.

The contracts with outside agencies allow either party to cancel with a 90-day written notice.

The Snohomish County Jail will continue to hold inmates who are already booked from King and Skagit counties but won’t accept any new bookings from them as of May 5.

“A changing inmate landscape — one that presents increasingly more individuals requiring (drug) withdrawal watches, more calls for medical care, and one that puts pressures on our mental health resources — requires us to take this step,” Trenary wrote.

Trenary also has hired a doctor to work at the jail. The next major step is forming a public advisory committee focusing on how the community should operate the jail, he said. That work is under way, and Trenary hopes to get the committee in place in March.

“We are absolutely making progress in the facility,” he said.

Nine inmates have died at the jail since 2010, most recently in January. The deaths have been attributed to a number of causes, including heart problems, suicide and overdose.

In some of the deaths, attorneys have filed multimillion-dollar claims alleging that inmates were denied basic medical care.

The stricter booking policies also have affected the city jails in Lynnwood and Marysville. Those communities have signed contracts with a jail in south King County to hold inmates they themselves are not equipped to house, including those who have medical problems or mental illness, or who need protective custody.

Rikki King: 425-339-3449; rking@heraldnet.com.